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effi src effi_erlang.erl
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src/effi_erlang.erl

%% -*- erlang -*-
%%
%% effi
%%
%% Copyright 2015-2018 Jörgen Brandt
%%
%% Licensed under the Apache License, Version 2.0 (the "License");
%% you may not use this file except in compliance with the License.
%% You may obtain a copy of the License at
%%
%% http://www.apache.org/licenses/LICENSE-2.0
%%
%% Unless required by applicable law or agreed to in writing, software
%% distributed under the License is distributed on an "AS IS" BASIS,
%% WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
%% See the License for the specific language governing permissions and
%% limitations under the License.
%%
%% -------------------------------------------------------------------
%% @author Jörgen Brandt <joergen.brandt@onlinehome.de>
%% @version 0.1.6
%% @copyright 2015-2018 Jörgen Brandt
%%
%%
%% @end
%% -------------------------------------------------------------------
-module( effi_erlang ).
-behaviour( effi ).
%%====================================================================
%% Exports
%%====================================================================
% effi callbacks
-export( [bind_singleton_boolean/2,
bind_singleton_string/2,
bind_boolean_list/2,
bind_string_list/2,
echo_singleton_boolean/1,
echo_singleton_string/1,
echo_boolean_list/1,
echo_string_list/1,
prefix/0,
end_of_transmission/0,
suffix/0,
process_script/1,
run_extended_script/2] ).
%%====================================================================
%% Includes
%%====================================================================
-include( "effi.hrl" ).
%%====================================================================
%% Effi callback function implementations
%%====================================================================
-spec bind_singleton_boolean( ArgName :: binary(), Value :: binary() ) ->
binary().
bind_singleton_boolean( ArgName, Value ) ->
<<ArgName/binary, " = ", Value/binary, ",\n">>.
-spec bind_singleton_string( ArgName :: binary(), Value :: binary() ) ->
binary().
bind_singleton_string( ArgName, Value ) ->
<<ArgName/binary, " = \"", Value/binary, "\",\n">>.
-spec bind_boolean_list( ArgName :: binary(), Value :: [binary()] ) ->
binary().
bind_boolean_list( ArgName, ValueLst ) ->
S = string:join( [binary_to_list( Value ) || Value <- ValueLst], ", " ),
B = list_to_binary( S ),
<<ArgName/binary, " = [", B/binary, "],\n">>.
-spec bind_string_list( ArgName :: binary(), Value :: [binary()] ) ->
binary().
bind_string_list( ArgName, ValueLst ) ->
S = string:join( ["\""++binary_to_list( Value )++"\"" || Value <- ValueLst], ", " ),
B = list_to_binary( S ),
<<ArgName/binary, " = [", B/binary, "],\n">>.
-spec echo_singleton_boolean( ArgName :: binary() ) ->
binary().
echo_singleton_boolean( ArgName ) ->
<<"io:format( \"", ?MSG, "{\\\"arg_name\\\":\\\"", ArgName/binary,
"\\\",\\\"value\\\":\\\"~p\\\"}~n\", [", ArgName/binary, "] ),\n">>.
-spec echo_singleton_string( ArgName :: binary() ) ->
binary().
echo_singleton_string( ArgName ) ->
<<"io:format( \"", ?MSG, "{\\\"arg_name\\\":\\\"", ArgName/binary,
"\\\",\\\"value\\\":\\\"~s\\\"}~n\", [", ArgName/binary, "] ),\n">>.
-spec echo_boolean_list( ArgName :: binary() ) ->
binary().
echo_boolean_list( ArgName ) ->
<<"io:format( \"", ?MSG, "{\\\"arg_name\\\":\\\"", ArgName/binary,
"\\\",\\\"value\\\":[~s]}~n\", [string:join( [if V -> \"\\\"true\\\"\"; true -> \"\\\"false\\\"\" end || V <- ",
ArgName/binary, "], \", \" )] ),\n">>.
-spec echo_string_list( ArgName :: binary() ) ->
binary().
echo_string_list( ArgName ) ->
<<"io:format( \"", ?MSG, "{\\\"arg_name\\\":\\\"", ArgName/binary,
"\\\",\\\"value\\\":[~s]}~n\", [string:join( [\"\\\"\"++V++\"\\\"\" || V <- ",
ArgName/binary, "], \", \" )] ),\n">>.
-spec prefix() ->
binary().
prefix() ->
<<"-module( __script ).\n-export( [main/1] ).\n\nmain( _ ) ->\n\n">>.
-spec end_of_transmission() ->
binary().
end_of_transmission() ->
<<"io:format( \"", ?EOT, "\\n\" ),\n">>.
-spec suffix() ->
binary().
suffix() ->
<<"ok.\n">>.
-spec process_script( Script :: binary() ) ->
binary().
process_script( Script ) ->
Script1 = string:trim( Script, trailing ),
Skip = byte_size( Script1 )-1,
case Script1 of
<<X:Skip/binary, ".">> -> <<X/binary, ",\n">>;
X -> <<X/binary, ",\n">>
end.
-spec run_extended_script( ExtendedScript :: binary(), Dir :: string() ) ->
{ok, binary(), [#{ atom() => _ }]}
| {error, binary()}.
run_extended_script( ExtendedScript, Dir ) ->
ScriptFile = string:join( [Dir, "__script.erl"], "/" ),
Call = "escript __script.erl",
ok = file:write_file( ScriptFile, ExtendedScript ),
Port = effi:create_port( Call, Dir ),
effi:listen_port( Port ).